Water Change Frequency

[msubhan]

There are 9 angel fish in 50 gallon tank. I feed them twice a day and do regular water change of 25 - 30% every week. Every Week when i test the water Nitrates is 5 to 10 PPM. Thinking of doing biweekly water change but am scared if Nitrates spikes.

Have also reduced feeding to control. Please let me know if I can do bi-weekly or continue weekly water change?

Attached the bed of my tank.

 

[tanker]

How big are your Angels?

 

[msubhan]

Attached fishes , it is medium sized

 

[OrionGirl]

You likely would be ok for just nitrates. Honestly, I'd see why your plants aren't eating up the nitrates. The issue would be that the angels are still growing and will therefore be producing more waste as they mature. Not sure what will happen in terms of aggression--that's a lot of angry fish in a 50.

ETA: keep in mind that nitrates are only the most easily testable of the pollutants in a tank. Those fish are also spewing out chemical warfare to keep each other in check, and reducing water change frequency would mean that built up, and you might see slower growth.

 

[msubhan]

it is not planted tank.

 

[FreshyFresh]

Like said, given the fish are growing and you are adding fish food to the tank ~14x per week, I would be doing closer to a ~75% WC per week. Or two 50% per week.

 

[dougall]

I would double check your nitrate test result and/or the amount you are feeding these growing fish.

 

[OrionGirl]

Ha, that's what I get for a quick look at the pick.

Adding plants would likely help. Without plants, I would stick with weekly.

 

[fishorama]

That's a LOT of angels in a smallish tank. I think they're small right now or you'd have seen death & mayhem by now. Angels seem to be delicate, but they're cichlids & will beat the living crap out of each other...until you're left with a (hopefully) compatible pair.

Plants are always good, but nothing will help too many angels in a smaller tank. Think of rehoming most of them soon.

 

[BillD]

I have to concur with the previous answers about the need for weekly, and, larger changes. My experience with angels is that you want to grow them as fast as possible. Once they get to breeding age, they will start fighting and/ or breeding,. so growth will slow down or stop. If I am growing out young angels, I feed numerous times daily. In the spring, when I have daphnia, I keep food in front of them 24/7, for all my fish that are small enough to eat them..With the heavier feeding comes the need for larger, and/or more frequent water changes. Your water can't be too clean.